Self closing flood barrier and method for protecting a hinterland using same

ABSTRACT

The flood barrier includes a chamber with a first side wall and a second side wall, a water inlet for letting in water, a single support block arranged on the first side wall, and a dam wall up and down movably arranged in the chamber. The dam wall forms a retaining wall for restraining water flow, a forcing element for causing an upward movement of the dam wall, and a blocking element for providing a blockade for limiting the upward movement, the blocking element. The support block has an inclined surface against which the inclined surface of the blocking element acts in a closed state of the flood barrier. Due to the orientation of the angled wall of the support block, the blocking element is forced to move sideward and thereby a lateral force is created forcing the dam wall to one side of the chamber.

The invention relates to a self closing flood barrier and a method forprotecting a hinterland against floods by means of such a self closingflood barrier.

Self closing flood barriers are known in which a dam wall is forcedupwards out of a chamber whenever the chamber fills up with water. Sucha flood barrier may be installed in for example a dike at a river side.The flood barrier automatically rises in the event of a flood, therebyprotecting the hinterland. As compared to conventional flood barriers,moveable flood barriers, also referred to as moveable dams, offer theadvantage that they constitute a dam only then when it is reallynecessary. In a normal situation, the dam is underground and invisiblefor the environment.

A moveable dam may comprise a vertical retaining wall which at itslowest side provided with a buoyant body housed in the chamber. Thebuoyant body forces the retaining wall out of the chamber through anopening at the top of the chamber. The buoyant body may also function asa blocking element in order to limit the upward movement of theretaining wall. In that case the buoyant body will be thicker than theupper opening of the chamber and is thereby prohibited to leave thechamber.

Publication EP 1950352 A2 discloses a flood barrier having a rectangularsupport block at one side of the chamber mounted to one of the chamberwalls. A buoyant body comprises a slightly inclined, nearly vertical,side surface which will result in the dam wall moving to the hinterlandside of the flood barrier in case of flooding. The buoyant body furthercomprises an extension at the bottom which abuts to the bottom of therectangular support block in case of flooding. Due to the specificstructure of the flood barrier, the retaining wall and the buoyant bodywill act as a lever wherein the water pressing against the water side ofthe retaining wall will try to tilt the floatable part. Due to thistilting, the maximum pressure between the floatable part and the chamberoccurs near the top of the chamber at the hinterland side, and betweenthe support block and the buoyant body at the water side. At both sidesa contact surface is very small. As a result, the flood barrier will beunstable in case of variable water pressure at the top of the retainingwall due to waves. Furthermore, the contact surfaces are subject to weardue to high and variable pressures.

It is a goal of the present invention to provide a flood barrier whichis more stable and more endurable than the barrier of the state of theart.

This goal is achieved by a self closing flood barrier for protecting ahinterland against floods, comprising:

-   -   a chamber comprising a first side wall and a second side wall;    -   a water inlet for letting in water;    -   a single support block arranged on said first side wall;    -   a dam wall member up and down movably arranged in said chamber,        the dam wall member comprising:        -   a retaining wall for avoiding water to flow to the            hinterland;        -   a forcing element for causing an upward movement of the dam            wall member, and        -   a blocking element for providing a blockade for limiting            said upward movement, said blocking element comprising an            inclined surface,

wherein said support block comprises an inclined surface against whichsaid inclined surface of said blocking element acts in a closed state ofsaid flood barrier.

In case water enters the chamber, the dam wall member will rise so thateventually the inclined surface of the blocking element is forcedagainst the inclined surface of the support block. This will result in asideward movement until the dam wall member abuts against the secondside wall of the chamber. In the closed state, the dam wall member hastwo contact surfaces, which results in reduced pressures as compared tothe barrier of the state of the art. This will result in less wear andmore stability of the total barrier.

By using only one support block, the dam wall member will be forcedagainst the hinterland side wall resulting in an improved sealing of thedam wall member. Also the usage of only one support block is cheaperthan having two support blocks. Furthermore, the usage of one supportblock will be favourable when having to maintain or repair the floodbarrier.

In an embodiment, the dam wall member comprises a substantially flatsurface facing said second side wall for abutment against said secondside wall. The flat surface is favourable because it makes the closedbarrier more stable.

In an embodiment, the flood barrier comprises a sealing member arrangedon said substantially flat surface near a lower outer end of said damwall member to avoid said water from flowing between said dam wallmember and said second side wall. Such a sealing member will improvesealing of the flood barrier and thereby preventing water from the waterside flowing to the hinterland side through the flood barrier in case ofa flood. Besides, a reduced water pressure at the second side of thewall member is realised and no tilting of the dam wall member occurswhich would otherwise move away the dam wall member from the chamberwall at its lower portion. Preferably the sealing member comprisesrubber or the like.

In a specific embodiment, the inclined surface of support block and saidinclined surface of said blocking element make, at least in use, anangle with the vertical, said angle having a value between 30°-60°, andpreferably equal to about 45°.

Preferably the support block is removably arranged on said first sidewall.

The support block may comprise a bottom which is connectable to saidfirst side wall of said chamber by way of connecting means.

The support block may further comprise a lockable entrance whichprovides access to the connecting means. In this way a maintenance teamcan have access to the connecting means in a very simple and effectiveway. The entrance can be opened after which one can disconnect theconnecting means and can remove the support block.

Preferably the inclined surface of blocking element transfers to a lessor non-inclined surface which is, at least in said closed state, distantfrom said first side wall of said chamber. In this way clamping of thedam wall member is minimized.

Preferably the blocking element, the forcing element and said retainingwall are one integrated part. This results in easy manufacturing andassembly.

The chamber of the self closing flood barrier may be arranged to beinstalled under the ground or partly under the ground, depending on thepurpose.

In an embodiment the chamber is substantially arranged under the groundand connected through a water inlet/outlet with a service pit.

Preferably the flood barrier comprises a lid for closing an opening ofsaid chamber, wherein said lid is fixed to an upper outer end off saiddam wall member. This lid may also function as an additional extensionof the flood barrier in case of a flood because it will prevent wavesfrom creeping over the outer top edge of the dam wall member. The lidwill function as a breakwater.

Finally, the invention also relates to a method for protecting ahinterland against floods by means of a self closing flood barrier asdescribed above, the method comprising:

-   -   providing the flood barrier described above;    -   bringing the flood barrier in a working state;    -   letting in of water in the chamber for forcing up the dam wall        member.

Embodiments of the invention will now be described, by way of exampleonly, with reference to the accompanying drawings in which correspondingreference symbols indicate corresponding parts, and in which:

FIG. 1 shows an embodiment of a flood barrier according to the inventionin a resting state;

FIG. 2 shows the embodiment of FIG. 1 in a closed state.

FIG. 3 schematically shows a cross section the chamber according to anembodiment;

FIG. 4 shows an embodiment in which the flood barrier comprises twoground load plates mounted on top of the side wall.

FIG. 1 shows an embodiment of a flood barrier according to the inventionas applied in a dike 1. FIG. 1 shows the flood barrier in a restingstate in which nearby water such as a river 10 has a normal water level.

In the embodiment of FIG. 1 the flood barrier comprises a chamber 3having a water side wall 20 and a hinterland side wall 21. The chamber 3also comprises a bottom 22 which connects the two sidewalls 20, 21respectively. The walls 20, 21 may be constructed out of sheet steel orany other suitable construction known to the skilled person, such asconcrete. In the chamber 3 a retaining wall 4 is present which issupported at its lowest side by a buoyant body 5. Preferably, theretaining wall 4 comprises polyester. This material reinforcement may befilled with foam as a sandwich construction and is very strong and alsovery light. In this embodiment, the flood barrier also comprises a lid 6fixed to the top of the retaining wall 4. The retaining wall 4 togetherwith the buoyant body 5 is also referred to as dam wall member. Pleasenote that the buoyant body 5 consists of two, preferably integrated,parts 5 a, 5 b and actually functions as both a forcing element forcausing an upward movement of the dam wall member, and as a blockingelement for limiting the upward movement.

Furthermore, the flood barrier may comprise a support block 7 removablyconnected to the water side wall 20 by means of a connecting means 15.In a very simple embodiment the connecting means comprise bolds 15. Inthis embodiment the support block 7 comprises an entrance 14 which isclosed by way of a cover 23. In an embodiment, the position at which thesupport block 7 is mounted to the side wall 20 is adjustable. In thisway, the opening of the chamber 3 can be adjusted to a desireddimension.

In this embodiment, the flood barrier further comprises a service pit 9which is connected to the chamber 3 by way of a water inlet/outlet 24.The water inlet 24 is connected to a vertical pipe 12 in the servicepit. The water inlet/outlet 24 comprises a valve 13 that is opened in acase the chamber 3 is emptied. In that situation the water inlet/outletfunctions as a water outlet 24. The service pit 9 is connected through achannel 11 to the water side of the dike 1 as shown in FIG. 1. The floodbarrier is practically invisible under normal water level conditions. Ontop, the lid 6 locks in the entrenchment space under normal conditions.

FIG. 2 shows the self closing flood barrier of FIG. 1 in a floodsituation wherein a flood is present resulting in a high water level ofthe river 10. Only after the water level of river 10 rises above theentrance level of pipe 12, the pipe and the water inlet 24 fill withwater resulting in a water stream towards the chamber 3. The water inchamber 3 will force the retaining wall 4 to move up because theretaining wall 4 together with the buoyant body 5 are floatable onwater. The dam wall member will move upwards until the buoyant body 5 isforced at its upper side against the angled wall 17 of the support block7. This will not only limit the upward movement of the dam wall 4 butwill also force the dam wall 4 against the hinterland side wall 21 ofchamber 3. As soon as the chamber 3 is totally filled, a closing seal 8will lock the barrier waterproof. Now the water can rise further withoutflooding the protected area, i.e. the hinterland.

By using the service pit 9, the flood barrier functions completelyautomatically without the need for controlled water inlet. Please notethat the service pit 9 also acts as a kind of water filter. Dirt and mudcoming from the river side will deposit at the bottom of the service pitand will not reach the chamber 3.

Preferably, the sealing member 8 is arranged on or at the flat side ofthe dam wall member, and preferable at the lower end of the dam wallmember. In FIG. 2, it can be seen that the sealing member 8 seals offthe space between the dam wall member and the hinterland side wall 21.In this way, the pressure between the hinterland side wall 21 and thedam wall member 4,5 is far less than the pressure between the water sidewall 20 and the dam wall member 4,5. This pressure difference willresult in a force that prevents a lever mechanism as mentioned in EP1950352 A2.

Once the water level subsides to a normal level, the chamber 3 isdrained through outlet 24 with one way check valves 13 or by means of apump (not shown). Once the water has left the chamber 3, the dam wallmember returns to its resting position within the chamber. The lid 6 ontop of the dam wall 4 then closes to prevent the inflow of waste ordebris. In FIG. 1 is shown that the dam wall member does not rest on afloor of the chamber 3. This results in a space in which mud and thelike may deposit. Such deposition will effectively raise the floor ofthe chamber 3 but this raising will not affect the resting position ofthe dam wall member. As a result, the lid will always close the openingof the chamber 3, even when dirt is present at the bottom of the chamber3. Furthermore, due to the weight of the dam wall member, the lid willbe presses downwards and will thus be closed due to the gravity forces.

Preferably, the lid 6 is arranged to support traffic and may be part ofa road surface, or a pavement.

Typical values for the height of the retaining wall 4 are 50 cm, 100 cm,150 cm, 200 cm or 250 cm. However higher flood barriers are possible.

Preferably the flood barrier comprises one or more seals 26,27, see FIG.2, for preventing dirt or waste, like waif wood, from flowing into thechamber at the upper entrance when the water level is falling.

FIG. 3 schematically shows a cross section the chamber according to anembodiment. The support block 7 is mounted at the inner side of thechamber wall 20. The inclined surface 17 of the support block 7 has anangle α with the vertical, which is preferably between 30-60°, and morepreferably about 45°. Preferably the same angle α is used for theinclination of the surface 16 on the buoyant body 5. These angles willresult in a smooth up and down movement of the dam wall member, withoutthe risk of the dam wall member getting stuck between the walls. Thisrisk is even further restricted by the fact that the buoyant body 5 hasa surface 19 that is distant from the inner side of the wall 20 in theclosed state.

FIG. 4 shows an embodiment in which the flood barrier comprises twoground load plates 41,42 mounted on top of the side wall 20,21. Theseplates will reduce the pressure at the outside of the chamber walls sothat the risk of the deformation of the chamber is decreased. Particularin situations wherein heavy traffic passes across the flood barrier, theplates 41,42 will be advantageous.

While specific embodiments of the invention have been described above,it will be appreciated that the invention may be practiced otherwisethan as described. For example, the invention may also be used toprovide a door for a garage or for closing/protecting any other entranceof a building. It may even be conceivable to provide water basins thewalls of which are formed by the flood barrier described above.

The descriptions above are intended to be illustrative, not limiting.Thus, it will be apparent to one skilled in the art that modificationsmay be made to the invention as described without departing from thescope of the claims set out below.

1. Self closing flood barrier for protecting a hinterland against floods, said flood barrier comprising: a chamber comprising a first side wall and a second side wall; a water inlet for letting in water; a single support block arranged on said first side wall; a dam wall member up and down movably arranged in said chamber, said dam wall member comprising: a retaining wall for avoiding water to flow to the hinterland; a forcing element for causing an upward movement of the dam wall member, and a blocking element for providing a blockade for limiting said upward movement, said blocking element comprising an inclined surface, wherein said support block comprises an inclined surface against which said inclined surface of said blocking element acts in a closed state of said flood barrier.
 2. Self closing flood barrier according to claim 1, wherein said dam wall member comprises a substantially flat surface facing said second side wall for abutment against said second side wall.
 3. Self closing flood barrier according to claim 2, wherein said flood barrier comprises a sealing member arranged on said substantially flat surface near a lower outer end of said dam wall member to avoid said water from flowing between said dam wall member and said second side wall.
 4. Self closing flood barrier according to claim 1, wherein said inclined surface of support block and said inclined surface of said blocking element makes, at least in use, an angle with the vertical, said angle having a value between 30°-60°, and preferably equal to about 45°.
 5. Self closing flood barrier according to claim 1, wherein said support block is removably arranged on said first side wall.
 6. Self closing flood barrier according to claim 5, wherein said support block comprises a bottom which is connectable to said first side wall of said chamber by way of connecting means.
 7. Self closing flood barrier according to claim 6, wherein said support block comprises a lockable entrance which provides access to the connecting means.
 8. Self closing water barrier according to claim 1, wherein said inclined surface of blocking element transfers to a less or non-inclined surface which is, at least in said closed state, distant from said first side wall of said chamber.
 9. Self closing water barrier according to claim 1, wherein said blocking element, said forcing element and said retaining wall are one integrated part.
 10. Self closing flood barrier according to claim 1, wherein said chamber is arranged to be installed under the ground or partly under the ground.
 11. Self closing flood barrier according to claim 10, wherein said chamber is substantially arranged under the ground and connected through a water inlet/outlet with a service pit.
 12. Self closing flood barrier according to claim 1, wherein said flood barrier comprises a lid for closing an opening of said chamber, wherein said lid is fixed to an upper outer end off said dam wall member.
 13. Method for protecting a hinterland against floods by means of a self closing flood barrier according to one or more of the preceding claims, said method comprising: providing said flood barrier; bringing said flood barrier in a working state; letting in of water in said chamber for forcing up said dam wall member. 